The Component Fatty Acids of Goat Milk Fat

Milk fats from different species of mammals are known to vary considerably in chemical composition. In early work, the butter fat constants were largely used to indicate the differences in composition. More recently, emphasis has been placed on comparisons of the component fatty acids of the various types of butter fats. The methods available for separation of the acids are not conducive to high precision. Their lack of uniformity, their dependence upon the manipulative technique, and upon the refinement of equipment have led to contradictory results and to differences of opinion as to the presence of certain acids. The distillation of the methyl esters is the most widely used method of effecting the separation of the components of butter fats. By the employment of this method and subsequent analyses of the distilled fractions, the presence of butyric, caproic, caprylic, capric, lauric, myristic, palmitic, stearic, and oleic acids in the fat of cow’s milk has been established without serious question. However, from time to time, other acids have been reported. Smedley (l), in 1912, inferred the presence of a Cl0 unsaturated acid after he obtained a maximum in the iodine number of a Cl0 fraction in his distillation data. Crow’ther and Hynd (2), in 1917, on the other hand, attributed the unsaturation of the lower fractions of butter esters to be due to oleic acid. Griin and Wirth (3), in 1922, isolated decenoic acid from the lower boiling acids and established the position of the double bond as the (9, 10) position. Bosworth and Brown (4), in 1933, made a detailed study of the component acids of butter fat of cow’s milk in which they, too, found decenoic acid. In addition they presented evidence indicating the presence of a number of other acids; namely, tetradecenoic acid, a C&o, C&,